Stuffing box



STUFF-ING BOX Filed Dec. 27, 193

'FEESPE' (6.36m BY ATTORN EY6 Patented Apr. 30,1940- UNl'lED STATES PATENT OFFlCE STUFFING BOX James S. Abercrombie, Houston, Tex. Application December 27,1937, Serial No. 181,834

6 Claims.

The invention relates to a balanced pressure stuffing boxwherein the pressure which is being packed against serves the purpose of maintaining a pressure to resist leakage. 5 Particularly in oil field equipment, abrasive liquids such as drilling muds 'must be pumped under enormous pressures. It is needless to say that a drilling mud is very abrasive and results in excessive wear upon rods, shafts and packings and it is with a view of providing a construction wherein a reserve of lubricant or non-abrasive liquid can be stored at a location adjacent the packing in such a manner that the pressure which is being packed against will be available 16 against this reserve of lubricant to balance the pressure of the abrasive liquid on the stufflng box or packing.

It is another object of the invention to provide a reserve of lubricant for stufling boxes which is stored in a resilient container subjected ,to the pressure which is being packed against.

Another object of the invention is to prevent wear on rods, shafts and packings by utilizing the pressure which is confined to'inject the lubricant into the packing and about the rod or shaft.

It is one of the objects of the..invention to provide a resilient sleeve container for lubricant for stufiing boxes.

Other and further objects of the invention will be readily apparent when the following description is considered in connection with the accompanying drawing, wherein the figure in the drawing illustrates a vertical sectional view of the structure for practicing the invention.

35 Pressures approximating 1500 and 2000 pounds per square inch are constantly maintained in the pumps for circulating this drilling mud as well as the swivels which support the drill pipe and conduct the mud into the well. There is consid- 40 erable leakage, due to the fact that the abrasive liquid will coat the rods and tubes or shafts of the parts-so that when there .is either reciprocation or rotation thereof,

sive liquid is of course under pressure, which tends to force'it into the packing so that in many instances the rods; and shafts or tubes will be quickly cut away as the packing becomes saturated with abrasive.

In order .to protect the packing and to introduce the lubricant therein, an attachment has been devised and, as seen in the drawing, the packing box is indicated generally at 2 and has been illustrated as either a portion of a slush pump, a drilling swivel or other pieces of equipthe abrasive will be 1 carried with the rod into the packing. This abra-.

ment wherein the rod, shaft or tube 3 is to be rotated or reciprocated relative to the stumng box 2. It will be understood that liquid or fluid under pressure is within the chamber 5 and it is intended that this abrasive liquid in the cham- 5 her 5 -will be excluded from the stumng box 2. It is to be understood that the member 3 may be hollow or solid.

A support or body I0 has an upstanding collar ll thereon which provides a recess l2 to receive the packing member I3. This packing'is held in position by a gland M which is adjustably received in the upper end of the collar II. The rod; shaft, or tubing 3 passes through the gland and the packing. v; 1

The support or body [0 may be fixed to a suitable structure l5 such as 'the housing of a swivel or a pump. It is to be understood, however, that the present invention may be applied at any desirable location where ,an abrasive is to be ex- .cluded from a packing assembly.

In the drawing the body I0 is shown as having been provided with a depending skirt or frame I! which may be made integrally of the body or may be connected thereto. This skirt has a plurality of spaced leg portions I8 extending therefrom which carry a collar IS. The legs l8 may be of any desired length, depending upon the volume of lubricant or non-abrasive substance which isto be deposited into chamber 2|. The skirt l1 and the head I! are each provided with an outstanding rib 22 which is so spaced as to provide an undercut groove 23. A resili nt sleeve 25 of rubber or other suitable material is adjusted about the skirt and head as well as the legs I8 and is provided. with an enlarged end 26 to fit into grooves 23. While this supporting frame 24 has been shown in the drawing as integral, it is obvious that it may be made in parts for purv pose of suitable assembly unless it is desired to expand the sleeve 25 and pass it over the head.

In order to close the lower end of the chamber 21 a porous packing 30 is disposed in the recess 31 and held in position by a gland 32.

In order that lubricant or other suitable nonabrasive liquid or fluid maybe injected into the chamber 2| a passage 35 has been shown in the support It). This passage leads into the opening 36 in the body l0 through which the rod or shaft 3 passes and may be controlled by a suitable 010- sure member 31 of any desired type.

In operation the parts will be assembled as shown in the drawing and a suitable volume of non-abrasive substance will be injected into the chamber 2| to fill the chamber and possibly to distend the sleeve 25 somewhat. The pressure at which this lubricant is injected will vary of course in accordance with the pressure which it is contemplated will be present in the chamber 5 and probably the pressure inside the chamber 2| will be at least equal to and possibly greater than the pressure in the chamber 5.

With the parts in this condition operation will begin and it seems obvious that the pressure in the chamber 5 will be exerted on the resilient sleeve 25 so as to force lubricant along the shaft 3 into the area of the packing 13. If there is any wear or vibration of the rod or shaft which would permit leakage through the stuffing box 2 then of course it will be the lubricant or non-abrasive liquid which will feed through the opening 36 and into the packing and 'it will be impossible for the abrasive material in the chamber 5 to reach the packing l3. This non-abrasive material will be constantly forced into the packing due to the resiliency of the sleeve 25 which is subjected to the pressure of the chamber 5. As leakage occurs the sleeve will gradually be forced to contract. Additional lubricant may be injected into the chamber 2| at desired intervals to replace the leakage.

There can be, no leakage of abrasive fluid inwardly around the shaft through the base l9 because the packing 30 is of a porous nature and the pressure thereon will be balanced inside and outside along the shaft 3 because of the resilient nature of the sleeve 25. The lubricant will pass along the shaft 3 and saturate the porous packing 30 and of course there will be no differential pressure along the shaft at this packing 30 be cause of the resilient nature of the sleeve 25.

From the foregoing it seems obvious that the pressure which is being packed against is utilized to maintain a seal of lubricant to prevent abrasion. I r

The large capacity of the chamber 2] will obviate frequent attention and when the device is once assembled and filled with lubricant it will operate for long periods of time because the lubricant will gradually be fed into the packing by the pressure being packed against.

What is claimed is:

l. A packing assembly including a support, a packing on one side thereof, a lubricant container on the other side thereof, means to introduce lubricant into said container, said container having a rigid frame and a resilient portion subjected to the pressure being packed against so that the lubricant is fed to said packing by such pressure, and a second packing on said container which is also subjected to the pressure of the lubricant.

2..A packing assembly including a pair of spaced packings, and a reservoir for lubricant,

\ said reservoir being disposed between said packings and having a rigid frame and a resilient portion so that the packed pressure will feed lubricant into said packings.

3. A packing assembly including a packing having a porous packing member, and a reservoir for lubricant, said reservoir including a rigid frame being disposed outside of said packing, a resilient portion on said reservoir subjected to the packed pressure so that the pressure on said packing will be balanced with the lubricant tending to prevent entrance of the packed pressure.

l. An attachment for lubricating packings comprising a frame, a resilient sleeve thereon, means to affix said frame at the inner end of the packing, a stuffing box at the end of said frame, and means to introduce lubricant inside of said sleeve so that such lubricant will be maintained at the pressure being packed against.

5. A housing containing fluid under pressure,

an opemngtherem, a rod or tubular member passing thru said opening and arranged for reciprocation or rotation, a stufiing box on the outside of said housing to form a seal about said member, a reservoir inside of said housing and about said member, said reservoir having a resilient portion yieldable against the pressure within said housing and a rigid portion to support said resilient portion, and means to introduce a non-abrasive'substance into said reservoir to be maintained therein under the pressure in said housing and to be fed into said stufling box by such pressure.

6. A housing containingfiuid under pressure, an opening therein, a rod or tubular member passing thru said opening and arranged for reciprocation or rotation, a stufiing box on the outside of said housing to form a seal about said member, a reservoir including a rigid frame inside of said housing and about said member, said reservoir having a resilient portion yieldable against the pressure within said housing, and means to introduce a non-abrasive substance into said reservoir to be maintained therein under the pressure in said housing and to be fed into said stuffing box by such pressure, and apacking about said member at the inside end of said reservoir to be subjected to the inside pressure of said'reservoir.

JAIVIES s. ABERCROMBIE. 

